Twenty years before Jurassic Park, Michael Crighton created another film about a high-tech fantasy theme park brought to its knees by science and technology run amok. Westworld was the writer-director’s first feature, and while it’s not as engrossing as the dino experience, older children and sci-fi lovers will still like this one.

As an overlong “commercial” tells us, Westworld is really one world in a three-world fantasy theme park that also includes Roman World and Medieval World. Here, bored vacationers of the future can pay $1000 per day to live out their fantasies as gunslingers, sheriffs, lords and ladies, or Roman nobles and slaves in worlds that are authentic in every detail. At the core of every theme park are a cadre of robots that look and behave exactly like people—even bleed like humans—except for one thing. “They haven’t perfected the hands yet,” re-visitor John (James Brolin) tells his first-timer friend Peter (Richard Benjamin).

Only hours into their fantasy experience, the two of them are having a drink at the saloon when a mean-looking hombre (Yul Brynner) knocks into Peter and ridicules him until, goaded by his friend, Peter engages him in a gunfight. He wins, of course, because at Westworld, as John reminds, the guests’ fantasies are always fulfilled.

Westworld is rated PG, but I’ll tell you right now that it’s more of a PG-13 film because of the violence that’s shown onscreen, along with some implied “lovemaking” at an 1880s-style brothel and at the other parks as well. The script focuses mainly on Westworld, where Eight Is Enough’s Dick Van Patten plays a banker whose fantasy is to do a little sheriffin’, but with a high-tech crew monitoring everything on screens we also get glimpses of what’s going on in the other worlds.

It’s fascinating to see some of the same themes explored in this 1973 film that Crichton later perfected in Jurassic Park. Some cheesy moments (is there a ‘70s movie that escaped them?) date the film, but Westworld is a fun futuristic thriller.

Aside from a trailer and a pilot for the short-lived (five episodes) 1980 TV series Beyond Westworld, the only bonus feature is a rough-looking period behind-the-scenes promo piece in which we see a 30-year-old Crichton at work on the set with his stars. Although an opening scene sports special effects that aren’t all that special, Westworld otherwise looks great on Blu-ray and is a solid addition to the body of films that offer cautionary tales about the limitations of science.